Sailing catamaran



ly 1954 M. L. MOFFITT, JR

SAILING CATAMARAN 4 Sheets-Sheet 1 Filed OGt. 2, 1962 FIG].

INVENTOR: I MERRITT L. MOFFITT, JR. M

ATTYS.

July 21, 1 64 v M. MOFFITT, JR 3,141,435

SAILING CATAMARAN Filed Oct. 2, 1962 4 Sheets-Sheet 2 INVENTORZ MERRITT L. MOF'FITT, JR.

ATTYS 4 Sheets-Sheet 5 M. L MOFFITT, JR

SAILING CATAMARAN ATTYS MERR I TT L. MOFFITT, JR. M

w wk QM QM m July 21, 1964 Filed Oct. 2,

July 21, 1964 M. L. MOFFITT, JR

SAILING CATAMARAN 4 Sheets-Sheet 4 Filed 001;. 2, 1962 INVENTOR;

BY MERRITT LW ATTYS United States Patent 3,141,435 SAILING CATAMARAN Merritt L. Moifitt, Jan, 9 Weirwood Road, Radnor, Pa. Filed Oct. 2, 1962, Ser. No. 227,903 8 Ciaims. or. 114 s9 The present invention relates generally to sailing catamarans and more particularly to a sailing catamaran characterized by a lightweight hull structure, a simplified rig, and a resiliently secured kick-up rudder assembly, the combination providing a high performance planing boat which may be easily and quickly disassembled for transport or storage.

The primary advantages of catamaran type sailboats, stability, speed and dryness, are in the usual construction Offset by disadvantages which include a complicated rigging arrangement and a bulky hull that is diificult to manage out of the water. In contrast, the present construction presents an unusually simple rig and is especially suited for car top portage inasmuch as the twin catamaran hulls are readily separable. The simplicity of the boat is such as to permit assembly, rigging and sailing of a small sized embodiment by a single person.

Accordingly, it is a primary object of the present invention to provide a catamaran hull construction which may be readily disassembled for maintenance, transportation, and storage.

A further object of the invention is to provide a catamaran having lightweight demountable deck elements secured to the hulls by adjustable and removable wire lacmgs.

An additional object of the invention is to provide a sailing catamaran, the mast supporting structure of which consists of an adjustable U-shaped yoke which does not interfere with the normal setting of the sails and which eliminates the need for an elaborate system of wire stays and shrouds.

A still further object of the invention is to provide a sailing catamaran having a simplified sliding gunter rig which is adaptable for reefing and which expedites the raising and lowering of the mainsail and eliminates the usual main halyard.

Another object of the invention is to provide a sailing catamaran as described having rubber shock absorbing compression plugs in each end of a tubular boom.

A still further object of the invention is to provide a sailing catamaran as described having a simplified resiliently secured kick-up rudder assembly which returns the rudder blade to its normal position following contact with underwater obstructions.

Additional objects and advantages of the invention will be more readily apparent from the following detailed description of an embodiment thereof when taken together with the accompanying drawings in which:

FIG. 1 is a side elevational view of a fully rigged embodiment of the invention;

FIG. 2 is a deck plan view of the embodiment taken along line 22 of FIG. 1;

FIG. 3 is a rear elevational view showing the embodiment with the jib removed;

FIG. 4 is a view taken along line 44 of FIG. 1 showing the masthead sliding gunter fitting;

FIG. 5 is a view taken along line 5-5 of FIG. 1 show- 3,141,435 Patented July 21, 1964 ing the manner in which the mast is secured to the sup porting yoke;

FIG. 6 is a sectional view taken along line 6-6 of FIG. 1 showing the manner in which the mast is stepped on the transverse mast supporting member;

FIG. 7 is a sectional view along line 7-7 of FIG. 6;

FIG. 8 is a sectional view along line 88 of FIG. 3 showing details of the adjustable mast supporting yoke;

FIG. 9 is a sectional view taken along line 99 of FIG. 2 showing the hull and deck assembly including the Wire lacing arrangement by which the decks are secured to the hulls;

FIG. 10 is a sectional view taken along line 10-10 of FIG. 9;

FIG. 11 is a sectional view showing a modified arrangement for securing the afterdeck assembly to a fiberglass hull;

FIG. 12 is a partly cutaway view showing the manner in which the lower end of the sliding gunter is secured to the mast, and details of the rubber shock absorbing boom P FIG. 13 is a view taken along line 1313 of FIG. 2 showing details of the rudder assembly;

FIG. 14 is a view taken along line 1414 of FIG. 13;

FIG. 15 is a view taken along line 1515 of FIG. 13 and;

FIG. 16 is a perspective of the rudder assembly with the rudder removed.

Referring to FIGS. 1, 2 and 3 of the drawings, the embodiment of the invention shown includes port and starboard hulls 10 and 12, mainsail 14, jib 16, mast 18, port and starboard daggerboards 20 and 22, and connected port and starboard rudder assemblies 24 and 26. The hulls are preferably of an undecked, unribbed lightweight synthetic molded construction. The extremely buoyant lightweight expanded polystyrene foams have been found to be well suited for this purpose.

The structure of the hulls, as seen most clearly in FIGS. 9-10 includes an integral molded daggerboard trunk 28 and a raised keelson 30 to provide longitudinal rigidity to the hulls and to serve as a foundation for deck attachment fittings. Exterior keel strips 32 are secured to the hulls by bolts 34 to protect the hulls from damage upon grounding of during dry storage. Wooden protective strips 36 on keelson 30 distribute the compressive force of the bolts along the keelson.

The gunwales 38 of the hulls are preferably formed in somewhat heavier cross section than the rest of the hulls to provide a substantial level surface upon which the removable decking is seated.

As may be seen in FIG. 2, each hull has a foredeck 40 terminating at edge 41 abaft the daggerboard trunk. Each foredeck, which may be of plywood or other suitable material, is fitted to conform with the outboard gunwale curvature of the hull. The inboard foredeck edge also follows the gunwale back to the mast, at which point it extends inwardly to the center line 42 of the assembled catamaran and aft along the center line to edge 41. The overhanging portions of the foredecks abutting along center line 42 serve to maintain the twin hulls in their proper separated parallel position.

As shown in FIG. 9, foredeck 40 is seated upon the gunwales 38 of the hull and is further supported by transverse deck beams 44 which are secured permanently to the underside of the foredeck and are carefully fitted transversely so as to butt against the inner surface of the gunwales 38 on each side of the hull.

Wire lacing 46 is alternately threaded through eyenuts 48 secured to bolts 34 along the keelson and through tangs 50 centrally secured to deck beams 4. Turnbuckle 52 at the after end of the lacing permits tightening of the lacing to the desired tension. Access to the lacing is provided by inspection ports 54 shown in FIG. 2.

Each foredeck is provided with a slot 56 in alignment with daggerboard trunk 28 to permit raising and lowering 'of the daggerboards 20 and 22. A similarly sloted member 58 of substantial thickness is secured to each foredeck over the slot to prevent deck wash from draining into the hulls through the slots and to strengthen the foredecks in the slot areas. Water entering the slotted member 58 drains through and out of the bottom of the centerboard trunk. Coaming 59 secured along edge 41 prevents wash from flowing into the cockpits.

Afterdeck assembly 60 includes afterdeck panel 62 which extends across the full width of hulls and 12. The panel is cut out to form port and starboard cockpits 64 and 66 and its outboard edges are curved to correspond with the outboard gunwales of the hulls when forward edge 68 of the panel abuts the after edge 41 of the foredecks 40.

The after deck panel 62, in contrast with the foredecks, does not rest directly on the gunwales but is supported upon transverse deck beams 70 which extend across the entire width of the catamaran. In addition to: beam 70, sheer strips 72 are secured to the underside of the afterdeck panel. The sheer strips are accurately curved to conform with and overlie both the inboard and outboard gunwales. Attached to the outer face of the sheer strips and extending therebelow over the gunwales, are aprons 74, preferably of sheet metal, which extend along the inboard and outboard gunwales of the hulls to secure the parallel disposition of the hulls. Flanges 76 directed inwardly along the lower edge of the apron 74 coact with the lower outer gunwale edge.

The afterdeck assembly is secured to the hulls by means of turnbuckles 78 which extend between eyenuts 80 on bolts 34 and tange 82 on deck beam 70.

The hulls, foredecks and afterdeck assembly are assembled in the following manner. Each foredeck is placed on its respective hull and the wire lacing 46 is threaded and secured by turnbuckles 52, access to the lacing being gained through inspection ports 54 and from the after end of the foredecks. The two hulls with foredecks securely laced in position are then placed side by side with the foredecks butting along the center line 42. The afterdeck assembly 60 is initially placed upon the after end of the hulls aft of its normal station with the aprons overlapping the gunwales. The assembly is then slid forward along the gunwales to its proper position abutting the foredecks and coamings, the aprons 74 guiding the hulls into their proper alignment. Turnbuckles 78 are attached and tightened to complete the afterdeck assembly installation.

Transverse mast support 83, which is preferably of a metal channel or box construction, is through-bolted to a deck beam to provide a foundation for the mast as well as to provide additional rigidity and strength to the hull assembly.

U-shaped bowsprit assembly 84 includes tubular deck members 86 which are permanently secured along the center line of each foredeck and extend beyond the bow of each hull. U-shaped tubular member 88 of a diameter smaller than that of member 86 is inserted into the open projecting ends of the members 86 and provides mounting means for the jib tack downhaul and an additional strengthening of the twin hull assembly. Bobstays 85 are included to further stiifen the assembly 84. The mast 18 is secured to transverse mast support 83 in the manner shown in FIGS. 6 and 7. The mast is of a tubular metal construction, the lower end 90 of which is pinched in a fore and aft direction so as to provide a transverse edge for seating the mast on the mast support to permit pivoting of the mast in a fore and aft plane. The mast end is not pinched shut, an opening remaining to permit the foot of the mast to be disposed over a U-bolt 92 secured to mast support 83. Bolt 94 is passed through the mast to engage the U-bolt and prevent disengagement of the mast from the mast support. The interacting bolts 02 and 94 permit a pivoting of the mast 18 in a fore and aft plane should variations in the rake thereof be desired.

The mast supporting means comprises a rigid, bowed, tubular yoke 96 which includes tubular port and starboard lower supports 98 and 100 into which telescopes bowed, tubular upper support member 102. The telescoping structure permits adjustment of the mast rake, the upper and lower support members being secured by pin 104 inserted in one of adjustment holes 105 in tube 102 as shown in FIG. 8.

The lower support members 98 and 100 are secured to the hull assembly in any suitable manner, preferably being anchored to a deck beam. The upper support member 102 is attached to the mast 18 by means of U-bolt 106 in the manner shown in FIG. 5. The U-bolt 106 is perpendicular to the plane of the upper support member 102 so that the mast 18 and the mast supporting yoke 96 may be folded into the same plane when the boat is not in use.

The bowed shape of the mast supporting yoke permits the mainsail to assume its normal shape when the boat is running before the wind. This non-interfering bowed shape permits anchoring of the lower supports 98 and 100 well aft of the mast step, thus taking the place of running backstays which might otherwise be necessary.

A sliding gunter arrangement is employed to support the mainsail. The gunter 108 is secured at the head 110 of mainsail 14 and extends within gunter pocket 111 in the luif of the mainsail approximately three-quarters of the way along the luff, terminating at lower end 112 extending below the gunter pocket. As shown in FIGS. 1 and 4, the gunter is slidably secured by masthead fitting 114 which is permanently attached to the head of the mast 18. Circular open slot 116 in the rafter overhanging portion of the masthead fitting is adapted to receive the gunter and mainsail from below and to allow the gunter to be slidably raised to its proper position.

Referring to FIG. 12, the lower end 112 of the gunter includes an angle gunter stud 118 which coacts with hole 120 in mast 18 to vertically secure the gunter in place against the normal downward force of the mainstail. The sail may be stretched downwardly by using conventional downhaul arrangements and in addition may be downwardly secured by lacing 122 at lower end 112 of the gunter.

The sliding gunter eliminates the need for a main halyard and thus greatly simplifies the rigging and unrigging of the sails. The mainsail is left on the boom and gunter when the sails are lowered. To raise the mainsail, the gunter is simply slid upwardly through slot 116 until stud 118 is engaged in hole 120. Should reefing be desired, such as with the roller reefing arrangement shown in FIG. 12, the gunter is slid downwardly through slot 116 in the masthead fitting and gunter stud 118 is placed in lower hole 124.

Shock-absorbing rubber compression plugs 126 and 128 are inserted in the tubular boom 130 and are expanded by tightening longitudinal through-bolts to form tightly secured boom end fittings which do not require, additional reinforcing of the boom ends or the drilling of holes therethrough which may tend to weaken the boom. Such a plug is adaptable for'use with a conventional combined sliding gooseneck and roller reefing fitting such as 132 by employing several through-bolts offset from the axis of the boom to compress the plug. The main sheet block and snap hook assembly 134 may be pivotally secured to extended bolt 136 axially disposed in plug 126 for compression thereof.

Jib 16 includes luff wire 138 which is fastened at its upper end in hole 140 of masthead fitting 114. The tack of the jib is downwardly secured by downhaul 142 which passes through block 144 on the bowsprit and back to a deck cleat, permitting jib luif adjustment while under Way.

Details of the kick-up rudder assembly are shown in FIGS. 13-16. Each assembly includes a rudder blade 144 preferably of one-piece wooden construction. Gudgeon straps 146 and 148 are bolted to the rudder blade 144 in parallel spaced relation as shown in FIG. 13. Tiller 150 is pivotally attached to rudder blade 144 by straps 152 and pin 154.

Centrally secured to the transom of each hull is bracket 156, the outwardly projecting arms 158 of which are bored to permit passage of horizontal rudder-supporting pin or bolt 160. Horizontal tube 162 is adapted to fit over pin 160 between arms 158 and serves as a bearing member for the kick-up rudder assembly. Sheet metal member 164 is formed to the U-shaped configuration shown and is drilled at its upper end to permit passage of horizontal tube 162. Member 164 when formed does not present a parallel-walled U-shape but is, in fact, more of a V-shaped configuration. The walls of member 164 are bent into paralled disposition to allow insertion of tube 162. When the bending pressure is released, the member 164 will, due to spring pressure, become secured in place on the tube 162.

As shown in FIGS. 13 and 16, member 164 extends vertically between the upper and lower gudgeon straps 146 and 148. With rudder blade 144 positioned so as to align the gudgeon straps with member 164 as shown, hollow pintle tube 166 is inserted through the gudgeon straps and members 164 to serve as an axis for rotation of the rudder blade. Bolt 168 passed through member 164 and engaged with a notch in pintle tube 166 prevents vertical movement of the pintle tube and holds the tube against the curved portion of member 164. As shown in FIG. 14, the relationship of the pintle tube to the horizontal tube 162 is such as to prevent fore and aft movement of the pintle tube in that region. Plate 169 on the hull provides a bearing surface for the forward lower edge of member 164.

As shown most clearly in FIGS. 13 and 16, an elastic shock cord 170 is led through pintle tube 166 and through opening 172 in the transom of the hull, the opening preferably being above the water line. The shock cord is secured at the upper end of the pintle tube such as by a knot to prevent passage of the cord end through the tube. Referring to FIG. 9, the inboard end 174 of the shock cord is secured inside the hull where it may be conveniently reached for adjustment. The end 174 of the cord may be adjustably secured by knotting and inserting in keyhole slot 176 in afterdeck panel 62.

As shown in FIGS. 2 and 3, the tillers of the port and starboard rudder assemblies 24 and 26 are linked by tie rod 178 to coordinate the steering effect of both assemblies.

The above-described rudder assembly construction cannot be damaged by grounding of the boat or the striking of an underwater obstruction. Upon encountering an obstacle, the entire assembly pivots about the pin 160 elongating shock cord 170. When the rudder has passed over the obstruction, the tension of the shock cord returns the assembly to its normal steering position.

The simplicity of the rudder assembly and the fabricating of most of the parts from stock materials and tubing results in low manufacturing and maintenance costs, with minimum weight.

The rudders may be quickly removed from the hulls by removing pins from the brackets 156 which permits removal of the entire assemblies other than the brackets. Shock cords must also be untied either from the hulls or from the pintle tubes 166.

A main advantage of the present catamaran construction is its adaptability to disassemble for transportation or storage. The standing rigging consists simply of the mast 18 and the bowed mast supporting yoke 96 which may be detached at their junctures with the deck and folded together. Tubular member 88 is detached from the deck members 86, mast support 82 is unbolted and removed from the foredecks, the rudder assemblies are removed in the manner described above, and the hulls are disassembled by detaching turnbuckle 78 and removing the afterdeck assembly 60. The foredecks 40 are separated from the hulls by removing wire lacings 46.

FIG. 11 shows a modified arrangement securing afterdeck assembly 60 to a fiberglass hull 178 having a flotation foam liner 180. L-bolts 182 inserted into deck beams 70 coact with slotted tangs 184 secured to the sides of the hull.

The disassembled boat may be transported on a standard car top carrier. In the smaller sized embodiments contemplated, disassembly and loading may be accomplished by a single person. Assembly and disassembly of the boat is facilitated by the absence of wire mast supporting stays, attachment and adjustment of which entail considerable time and effort in the usual small boat rig. An additional time saving feature is the sliding gunter rig which provides a foolproof non-fouling sail raising means, eliminating sheaves, cleats and halyards and permitting fast reefing or removal of the mainsail in a squall or other emergency situation.

The present catamaran has demonstrated an ability to plane in moderate winds in which other planing-type boats remain deep in the water. The remarkable planing performance of the design can be attributed to the extremely lightweight hull and rigging construction illustrated and described herein.

Manifestly changes in details of construction can be effected by those skilled in the art without departing from the spirit and the scope of the invention as defined in and limited solely by the appended claims.

I claim:

1. A sailing catamaran comprising a pair of undecked hulls, a deck assembly extending transversely across said pair of hulls, said deck assembly having aprons extending downwardly therefrom to maintain said hulls in parallel alignment, and removable adjustable tension members securing said deck assembly to said hulls; a mast supporting a sail and a hollow boom, a rigid yoke secured to each of said hulls at a point aft of said mast and attached to said mast to provide longitudinal and transverse support thereto, said yoke having an outwardly bowed configuration to minimize interference with the sail and boom; a sail mounting arrangement comprising a gunter attached to the luff of the sail, a masthead fitting adapted to slidably secure said gunter, a stud in the lower end of said gunter, and a hole in the mast to receive said stud, the sail being raised by inserting said attached gunter through said masthead fitting and sliding said gunter upwardly until said stud engages said hole; resilient compression plugs on the ends of the boom for attachment of fittings thereto, said compression plugs fitting snugly within the hollow boom ends, at least one throughbolt longitudinally disposed through each of said plugs providing longitudinal compression and radial expansion of said plugs and frictionally securing said plugs to the boom ends; a resiliently secured rudder assembly on each of said hulls comprising a rudder blade, a tiller, means operatively connecting said tiller with said rudder, spaced parallel gudgeon straps attached to said rudder, a U-shaped member extending so as to fit between said spaced parallel gudgeon straps on said rudder, a pintle tube passing through said gudgeon straps and said U1 shaped member, means securing said pintle tube in' said gudgeon straps and U-shaped member, and means securing the upper end of said U-shaped member in vertically pivotable relation to a hull, and a shock cord secured at one end to the hull and at the other end to said rudder assembly, the assembly permitting vertical pivoting of said rudder blade thereby avoiding rudder damage upon striking of underwater obstructions, said shock cord returning said rudder blade to its normal steering position following vertical pivoting, and retaining the blade in that position during normal steering operation thereof.

2. A sailing catamaran comprising a pair of undecked hulls, foredecks on each of said hulls, removable adjustable tension members securing said foredecks to said hulls, said foredecks abutting so as to dispose said hulls in the parallel spaced alignment, an afterdeck assembly extending transversely across said pair of hulls and having aprons extending downwardly therefrom to maintain the parallel alignment of said hulls, removable adjustable tension members securing said afterdeck to said hulls, disassembly of said hulls, afterdeck and foredecks being readily effected by removal of said tension members for transportation or storage of the catamaran; a mast supporting a sail and a hollow boom, a rigid yoke secured to each of said hulls at a point aft of said mast and attached to said mast to provide longitudinal and transverse support thereto, said yoke having an outwardly bowed configuration to minimize interference with the sail and boom; a sail mounting arrangement comprising a gunter attached to the luff of the sail, a masthead fitting adapted to slidably secure said gunter, a stud in the lower end of said gunter, and a hole in the mast to receive said stud, the sail being raised by inserting said attached gunter through said masthead fitting and sliding said gunter upwardly until said stud engages said hole; resilient compression plugs on the ends of the hollow boom for attachment of fittings thereto, said compression plugs fitting snugly within the hollow boom ends, at least one throughbolt longitudinally disposed through each of said plugs providing longitudinal compression and radial expansion of said plugs and frictionally securing said plugs to the boom ends; a resiliently secured rudder assembly on each of said hulls comprising a rudder blade, a tiller, means operatively connecting said tiller with said rudder, spaced parallel gudgeon straps attached to said rudder; a bracket secured to the transom of a hull, a pin horizontally secured by said bracket, a tube horizontally journalled on said pin, a U-shaped member drilled to receive said tube in perpendicular relation through the upper end thereof, said U-shaped member being formed so as to grip said tube by spring pressure of its opposing side walls, said U-shaped member extending so as to fit between said spaced parallel gudgeon straps on said rudder, a pintle tube passing through said gudgeon straps and said U-shaped member, a bolt passing through said U-shaped member engaging a notch in said pintle tube to secure said tube in said U-shaped member, and a shock cord secured at one end to the hull and at the other end to said rudder assembly, the assembly permitting vertical pivoting of said rudder blade above said horizontal tube thereby preventing rudder damage upon striking of underwater obstructions, said shock cord returning said rudder blade to its normal steering position following vertical pivoting, and retaining the blade in that position during normal steering operation thereof.

3. A catamaran comprising a pair of undecked hulls having gunwales extending outwardly therefrom, a deck assembly extending transversely across said pair of hulls, said deck assembly having aprons extending downwardly therefrom to maintain said bulls in parallel alignment, inwardly directed flanges on said aprons coacting with said gunwales, and removable adjustable tension members securing said deck assembly to said hulls, a mast supported upon said deck assembly, and a rigid yoke secured to each of said hulls at a point aft of said mast and attached to said mast toprovide longitudinal and transverse support thereto, said yoke having an outwardly bowed configuration to minimize interference with a sail and boom supported by said mast. 1

4. A sailing catamaran comprising a pair of undecked hulls, foredecks on each of said hulls, an adjustable wire lacing securing each of said foredecks to said hulls, said foredecks abutting so as to disposed said hulls in parallel spaced alignment, an afterdeckrassembly extending transversely across said pair of hulls and having aprons extending downwardly therefrom to maintain the parallel alignment of said hulls, said hulls having gunwales extending outwardly therefrom, inwardly directed flanges on said aprons coacting with said gunwales, the coaction of said hulls gunwales and said afterdeck assembly apron flanges permitting a sliding interlocking assembly of said hulls and afterdeck assembly, removable adjustable ten sion members maintaining the fore and aft position of said afterdeck assembly relative to said hulls, disassembly of said hulls, afterdeck and foredecks being readily eifected by removal of said tension members for transportation or storage of the catamaran; a mast supporting a sail and boom, a rigid yoke secured to each of said hulls at a point aft of said mast and attached to said mast to provide longitudinal and transverse support thereto, said yoke having an outwardly bowed configuration to minimize interference with the sail and boom.

5. A catamaran comprising a pair of undecked hulls, the gunwales of said hulls extending outwardly therefrom, a deck assembly extending transversely across said pair of hulls, said deck assembly having aprons extending downwardly therefrom to maintain said hulls in parallel alignment, inwardly directed flanges on said aprons engaging the lower edges of said gunwales, and removable adjustable tension members securing said deck assembly to said hulls, whereby said hulls and deck assembly may be readily disassembled by removal of said tension members for transportation or storage of the catamaran.

6. A catamaran comprising a pair of undecked hulls, foredecks on each of said hulls, an adjustable wire lacing securing each of said foredecks to said hulls, said foredecks to said hulls, said foredecks abutting so as to dispose said hulls in parallel spaced alignment, an afterdeck assembly extending transversely across said pair of hulls and having aprons extending downwardly therefrom to maintain the parallel alignment of said hulls, said hulls having gunwales extending outwardly therefrom, inwardly directed flanges on said aprons coacting with said gunwales, the coaction of said hull gunwales and said afterdeck assembly apron flanges permitting a sliding interlocking assembly of said hulls and afterdeck assembly, and removable adjustable tension members maintaining the fore and aft position of said afterdeck assembly said afterdeck to said hulls, whereby said hulls, afterdeck and foredecks may be readily disassembled by removal of said tension members for transportation or storage of the catamaran.

7. A sailing catamaran comprising a pair of undecked hulls, foredecks on each of said hulls, removable adjustable tension members securing said foredecks to said hulls, said foredecks abutting so as to dispose said hulls in parallel spaced alignment, an afterdeck assembly extending transversely across said pair of hulls and having aprons extending downwardly therefrom to maintain the parallel alignment of said hulls, removable adjustable tension members securing said afterdeck to said hulls, disassembly of said hulls, afterdeck and foredecks being readily effected by removal of said tension members for transportation or storage of thecatamaran; a mast supporting a sail and boom, a rigid yoke secured to each of said hulls at a point aft' of said mast and attached to said mast to provide longitudinal and transverse support thereto, said yoke having an outwardly bowed configuration to minimize interference with the sail and'boom, said yoke com prising a bowed, inverted U-shaped upper support member and lower tubular support members, and means permitting telescoping of said upper and lower support members for adjusting the rake of the mast.

8. In a sailing catamaran having parallel hulls and a mast supporting a sail and boom, the improvement comprising a rigid yoke secured to each of said hulls at a point aft of the mast and attached to the mast to provide longitudinal and transverse support thereto, said yoke having an outwardly bowed configuration to minimize interference with the sail and boom, said yoke comprising a bowed, inverted U-shaped upper support member and lower tubular support members, and means permitting telescoping of said upper and lower support members for adjusting the rake of the mast.

References Cited in the file of this patent UNITED STATES PATENTS Coles Apr. 14, Jones Aug. 2, Wilkie Dec. 5, Jones Mar. 17, OHiggins July 5, De Long June 12,

FOREIGN PATENTS Sweden Apr. 12, Great Britain Sept. 7, 

8. IN A SAILING CATAMARAN HAVING PARALLEL HULLS AND A MAST SUPPORTING A SAIL AND BOOM, THE IMPROVEMENT COMPRISING A RIGID YOKE SECURED TO EACH OF SAID HULLS AT A POINT AFT OF THE MAST AND ATTACHED TO THE MAST TO PROVIDE LONGITUDINAL AND TRANSVERSE SUPPORT THERETO, SAID YOKE HAVING AN OUTWARDLY BOWED CONFIGURATION TO MINIMIZE INTERFERENCE WITH THE SAIL AND BOOM, SAID YOKE COMPRISING A BOWED, INVERTED U-SHAPED UPPER SUPPORT MEMBER AND LOWER TUBULAR SUPPORT MEMBERS, AND MEANS PERMITTING TELESCOPING OF SAID UPPER AND LOWER SUPPORT MEMBERS FOR ADJUSTING THE RAKE OF THE MAST. 